Developer FAQ
From MoodleDocs
Moodle's database
Where can I see a schema for the structure of the Moodle database?
When installing Moodle, the database tables are generated and updated by various db-handling scripts located in various places. There is no canonical schema representation, although the coding guidelines for database structure give an outline of the general approach.
How to get/set information when writing new Moodle code
How do I find out the currently-logged-on user?
The global object $USER, which contains the numeric $USER->id among other things.
How do I find out the current course?
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How do I insert/retrieve records in the database, without creating my own database connections?
Always use the "datalib" functions, such as insert_record() or get_record(). This helps with database abstraction (e.g. running on either MySQL or Postgres) as well as maintaining a single database connection. Moodle uses ADODB for database abstraction.
Look at the documentation for datalib.php for the list of functions and details of use.
How do I get/set configuration settings?
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